Risk Assessment

List of Figures xiii
List of Tables xvii
Acknowledgments xxi
1 Introduction to Risk Assessment 1
1.1 Terminology, 6
1.2 Performing Risk Assessments, 6
1.3 Risk Assessment Team, 7
1.3.1 Team Approach, 7
1.3.2 Team Representatives, 10
References, 11
2 Risk Perception 13
2.1 Knowledge Level, 15
References, 20
3 Risks and Consequences 21
3.1 Introduction, 21
3.2 Risk and Consequence, 21
3.3 Credible Consequences, 24
3.4 Summary, 25
References, 25
4 Ecological Risk Assessment 26
4.1 Introduction, 26
4.2 Deep Water Horizon, 29
4.3 Love Canal, 34
4.4 Minimata Methylmercury, 36
4.5 Agent Orange, 38
4.6 Seveso, Italy, 40
4.7 Risk of Ecological Disasters, 41
4.8 Ecological Risk Assessment, 41
4.8.1 Example Ecological Risk Assessment, 45
4.9 Summary, 53
References, 54
5 Task Analysis Techniques 56
5.1 What is Task Analysis? 56
5.2 Why a Task Analysis? 57
5.3 When to use Task Analysis? 58
5.4 Task Analysis Process, 58
Step 1: Data Collection Information, 59
Step 2: Recording the Data, 60
Step 3: Data Analysis, 63
References, 63
6 Preliminary Hazards Analysis 64
6.1 Description, 65
6.1.1 Process of Preliminary Hazards Analysis, 66
6.1.2 Hazard Class, 69
6.1.3 Examples of Hazardous Energy Sources, 69
6.2 Using Process Hazard for Procedure Design, 72
6.2.1 Purpose of Process, 72
6.2.2 Initial Basic Procedure Steps, 72
6.2.3 Analysis, 73
6.2.4 Using the Results of the Analysis, 73
6.3 Using PHA for Preliminary Product Design, 75
Step 1: Determine Functions of the Crib, 76
Step 2: Determine Required/Critical Specifications, 76
Step 3: Determine Major Systems/Subsystems of the Crib, 76
Step 4: Determine Important Components of Each System/Subsystem, 77
Step 5: Determine Operating Modes of the Crib, 77
6.4 Summary, 79
References, 79
7 Primer on Probability and Statistics 81
7.1 Introduction, 81
7.2 Probability Theory, 85
7.3 Combining Probabilities, 87
7.4 Conditional Probability, 88
7.5 Probability Distributions, 89
7.6 Using Probability, 92
7.7 Summary, 95
References, 96
8 Developing Probabilities 97
8.1 Risk Assessment Data, 97
8.1.1 Introduction, 97
8.1.2 Hardware Failure Rate Data, 97
8.1.3 Manufacture, 98
8.1.4 Historical Data, 98
8.1.5 Government and Military Handbooks, 98
8.1.6 Commercial Data Sources, 98
8.1.7 Operational Data and Testing, 99
8.1.8 Failure Rate Calculations, 100
8.1.9 Accident Data, 103
8.1.10 Monte Carlo Simulation, 106
8.1.11 Human Error Probabilities, 107
8.1.12 Delphi Method, 108
8.1.13 Summary of the Delphi Process, 115
8.2 Overall Summary, 116
References, 116
9 Failure Mode and Effects Analysis 118
9.1 Introduction, 119
9.1.1 Description, 119
9.1.2 Why is a Failure Mode and Effects Analysis Effective? 119
9.1.3 Types of Failure Mode and Effects Analyses, 120
9.1.4 Failure Mode and Effects Analysis Process, 120
9.2 Summary, 134
References, 134
10 Human Reliability Analyses 135
10.1 Introduction, 135
10.1.1 Purpose, 135
10.1.2 Background, 135
10.1.3 Bounding the System, 136
10.1.4 Summary Points, 139
10.2 Task Analysis, 139
10.2.1 Summary Points, 140
10.3 HRA Modeling, 141
10.3.1 Summary Points, 143
10.4 Quantifying Human Error Probability (HEP), 144
10.4.1 Summary Points, 148
10.5 Documentation, 148
10.5.1 Summary Points, 149
10.6 Use of Human Reliability Analysis Techniques for Analyzing Procedures, 149
10.6.1 Procedure, 149
10.6.2 Procedure with Inspection Steps, 151
References, 151
11 Critical Incident Technique 153
11.1 Introduction, 153
11.2 Method, 153
11.3 Building on the Results of a Critical Incident Technique Session, 157
Step 1: Ramp Agent observes Anomaly on Aircraft Cargo Door, 158
Step 2: Ramp Agent Discusses Damage with Supervisor, 160
Step 3: Ramp Agent Discusses Decision to Report Damage to Maintenance Control with
Supervisor, 160
Step 4: Ramp Agent Decides to Report Damage to Maintenance Control, 161
Step 5: Ramp Agent Shows Maintenance Control the Damage, 161
11.4 Summary, 162
References, 162
12 Event Tree and Decision Tree Analysis 163
12.1 Event Trees, 163
12.1.1 Case Study, 167
12.2 Decision Trees, 168
12.2.1 Problem, 170
12.3 Case Study: Chernobyl, 175
12.3.1 Analysis of the Event, 178
12.3.2 Event Tree Analysis, 179
12.4 Summary, 180
References, 180
13 Critical Function Analysis 181
13.1 Introduction, 181
13.1.1 United Flight 232, 183
13.1.2 Air Canada Flight 143, 185
13.2 Critical Functions, 187
13.3 Conducting a Critical Function Analysis, 190
13.3.1 Critical Function of a Small Business, 192
13.3.2 Chemical Reactor Critical Function Analysis, 193
13.3.3 Emergency Management Planning, 195
13.4 Summary, 197
References, 201
14 Basic Fault Tree Analysis Technique 203
14.1 History, 203
14.2 Application, 204
14.3 Fault Tree Construction, 205
14.4 Event Symbols, 205
14.5 Logic Gates, 207
14.6 Analysis Procedure, 208
14.6.1 Defining the Problem, 208
14.6.2 Constructing the Fault Tree, 209
14.6.3 Analyzing the Fault Tree, 210
14.6.4 Documenting the Results, 211
14.7 Examples of Fault Tree Analysis, 211
14.7.1 Simple Example, 211
14.7.2 Modeling Success Using Fault Tree Analysis, 214
14.7.3 Fault Tree Analysis for Use in Accident Investigation, 215
14.8 Summary, 221
References, 221
15 Probabilistic Risk Assessment 223
15.1 Description, 223
15.2 Requirements of the Risk Assessment, 224
15.3 Simplified PRA Procedure, 224
15.4 Hazard Identification and Evaluation, 225
15.5 Qualitative Risk Assessment, 225
15.6 Quantitative Risk Assessment, 226
15.7 Uses of PRA, 229
15.8 Conclusion, 230
References, 230
16 Qualitative and Quantitative Research Methods Used in Risk Assessment 231
16.1 What is Qualitative Research? 231
16.1.1 Narrative Research, 232
16.1.2 Phenomenological Description, 233
16.1.3 Grounded Theory Research, 234
16.1.4 Ethnographic Research, 235
16.1.5 Case Study Research, 236
16.2 Quantitative, 238
16.3 Risk Assessment Perspective, 240
16.3.1 Aviation Study, 241
16.3.2 Design, 245
16.4 Conclusion, 247
References, 247
17 Vulnerability Analysis Technique 249
17.1 Introduction, 249
17.2 Case Study 1: Intruder, 251
17.3 Case Study 2: Multipurpose Academic Building, 254
17.3.1 Methods of Collecting Information, 255
17.3.2 Task Analysis, 257
17.3.3 Risk Assessment, 259
Reference, 276
18 Developing Risk Model for Aviation Inspection and Maintenance Tasks 277
18.1 Introduction, 277
18.2 Failure Mode and Effect Analysis, 277
18.3 Event Tree and Fault Tree Analysis, 279
18.4 Summary, 290
References, 291
19 Risk Assessment and Community Planning 292
19.1 Introduction, 292
19.2 Example Analysis, 296
19.2.1 Preliminary Hazard Analysis for Site A, 298
19.2.2 Preliminary Hazard Analysis for Site B, 298
19.2.3 Preliminary Hazard Analysis for Site C, 303
19.3 Summary, 307
References, 307
20 Risk of an Epidemic 309
20.1 Introduction, 309
20.2 Plague Example, 311
20.3 Tularemia Example, 312
20.4 Anthrax Example, 312
20.5 Ebola Example, 313
20.6 Smallpox Example, 313
20.7 TB Example, 314
20.8 Typhoid Fever Example, 314
20.9 Influenza Example, 315
20.10 Example of Measles, Mumps, and Rubella, 315
20.11 Polio Example, 316
20.12 Pertussis (Whooping Cough), 316
20.13 Cholera Example, 317
20.14 Summary, 318
References, 318
21 Process Plant Risk Assessment Example 319
21.1 Introduction, 319
21.1.1 Phillips Houston Chemical Complex, 319
21.1.2 BP Texas City Refinery, 323
21.2 Example Analysis, 327
21.2.1 Preliminary Hazard Analysis, 331
21.2.2 Sample Failure Mode and Effect Analysis, 334
21.2.3 Sample Event Trees, 334
21.2.4 Sample Fault Trees, 334
21.2.5 Sample PRA, 334
21.3 Summary, 344
References, 344
22 Industry Specific Case Studies 346
22.1 Case Study 1: Overview, 346
22.1.1 Introduction, 347
22.1.2 Approach, 349
22.1.3 Summary, 354
22.2 Case Study 2: Overview, 354
22.2.1 Introduction, 355
22.2.2 Approach, 356
22.2.3 Conclusions, 359
22.3 Case Study 3: Overview, 362
22.3.1 Introduction, 363
22.3.2 Purpose Statement, 363
22.3.3 Airport Security Risk Assessment Process, 364
22.3.4 Summary, 369
22.4 Case Study 4: Overview, 369
22.4.1 Introduction, 369
22.4.2 Food Safety Risk Assessment, 371
References, 375
23 Restaurant Risk Assessment Case Study 376
23.1 Introduction, 376
Glossary 381
Acronyms 386
Index 389